For the production of such gases, the extraction output is generally the preponderant parameter. To maximize performance, the durations of the different steps are chosen to be sufficiently long that the adsorbents operate at equilibrium, which is to say in which there is no kinetic limitation. The duration of adsorption for an adsorber is thus typically of the order of 2 to 4 minutes for total cycle durations generally greater than 10 minutes.
So as to increase the output, numerous PSA adsorption cycles comprising, in the course of the regeneration phase, several successive pressure balancings, have been proposed.
However, this latter technique is costly of capital, because it requires installing a large number of adsorbers each having an increased size. Moreover, this increased investment is particularly penalizing when the maximum demand for the production gas is only temporary.